Perhaps some of us value our freedom?
Perhaps some of us find that it helps to develop on the same platform on which we deploy?
Perhaps some of us find that we don't, actually, spend all that much time on 'admin, busy-work type issues,' having decided on good, solid distros which fit our use cases (Debian works for me, others prefer RedHat)?
At the end of the day, though, it really is about freedom for me. You complain that you must tweak your system; I value that I can tweak mine.
For instance, take sloppy focus. On my Linux machines, I can type in one window while interacting with another, and I use that ability fairly often. On my Mac, I have to spend time resizing and rearranging windows because I have to click a window to type there, and clicking raises it to the foreground, obscuring my other windows. Does the amount of time I spend managing windows outweigh the configuration time for the Linux box? I doubt it. But the end result is that my Linux machine feels like I built it exactly to spec. I value the fact that my OS, window manager, etc. do exactly what I want them to do in the same way that many people value the trackpad. I'm absolutely as annoyed and frustrated by the fact that the maximize/fullscreen button on my OS X windows moves my window to Space N+1 instead of keeping it where it is where a quick Cmd-Tab would bring a background window quickly back on top of the still-visible fullscreen window than I am that the trackpad on my Arch Linux box is less reliable at interpreting a gesture.
You know kinda like you do with apple machines.
everything i have worked out of the box. and, as a plus, android usb tethering works a lot better on linux than on osx (thanks to networkmanager)